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Authorized by Hanban, HSK Standard Course is developed under the joint efforts of Beijing Language and Culture University Press and Chinese Testing International (CTI). With HSK test papers as its primary source, HSK Standard Course is characterized by a humorous style, familiar topics and a scientific course design. This is Textbook 4, which includes 20 lessons and covers 600 words and language points required by the HSK Level 4 test. Upon finishing this book, students will be able to pass the HSK Level 4 test and their Chinese proficiency will reach the corresponding level.